Cheers,

the Question is straight forward and I wonder if it has been answered already.

I do wonder what the vague wording of Guerilla Training (First Founding P.18) actually refers to.

- It is pretty obvious that it negates the -30 Penalty due to AP

- Yet does it also negate the -10 due to Hulking?

Imho the later is also affected for the Astartes Power Armor has no inherent Concealment/Silent Move penalty. All its penalties are deducted from either having a stat (AP) above a threshold that is covered by a general rule outside the entry or from granting a Trait that is also covered by a general rule. Between these two penalties there is no difference in quality.

Furthermore Astartes are not hulking on their own, only due to wearing their Power Armor and thus the causation for that penalty is strictly connected to wearing that armor - just as much as going over a certain AP limit -, resulting in this also being negated by Guerilla Training.

Listed among the effects granted by wearing Power Armour (Core p. 161.) is this one:

Giant Among Men : A Space Marine in power armour is Hulking. This increases his Base Movement by 1; however, the grace afforded by his Black Carapace negates the modifier enemies would otherwise have to attack him. See page 134 for the full effects of Size. He still suffers the usual penalties to Concealment and Silent Move for being heavily armoured.

So the Hulking trait is granted by wearing Power Armour, and normally all its drawbacks are in effect except the one negated by the Black Carapace. The Guerilla Training negates additional negative effects.

Well, it says "The Battle Brother does not take the penalties to Silent Move and Concealment normally inflicted by power armour.". As the size is also a penalty originating from the power armour, I'd say this gets negated as well.

Maybe it's me, but apparently I don't get what's the question. The Size penalty (technically the +10 to BS or WS opponents would get) is already negated by the Black Carapace for all Marines. In addition to that, the Guerilla training negates the -10 penalties for Concealment and Silent Move. What else is unclear?

The Size penalty is already negated by the Black Carapace for all Marines.

As far as I read the description, the Black Carapace negates the modifier to attack roles, not the penalty to concealment (might argue about that one) and silent move.

As far as I read the description, the Black Carapace negates the modifier to attack roles, not the penalty to concealment (might argue about that one) and silent move.

Hmm, fair enough, that was lousy and inattentive reading in my part - indeed, the penalties to Silent Move and Concealment are also coming from the Size modifier. That's clear then.

On the other hand, what's the "-30 Penalty due to AP" the OP talks about? For the life of me, I can't figure out what AP stands for in this context.

AP (Armour Points): How many Armour Points the armour provides for the locations covered. Any armour that provides 7 or more APs inflicts a -30% penalty on the wearer’s Concealment and Silent Move Tests.

From the Armory section of every 40k RPG released to date.

Ouch. I completely missed that section, despite my many years of GMing in multiple 40k systems - thanks for pointing it out! That means that standard Marines all get a -40 to all Concealment and Silent Move tests. Hmm, my team won't like that

In this case OP is right. Guerilla Training says "The Battle-Brother does not take the penalties to Silent Move and Concealment normally inflicted by power armour" - that must include the -30 for wearing a 7+ AP armour.

Yeah, that's why even with a masking screen sneaking is hell for a marine (except raven guard). Took me ages to make a scenario where my KT decided that they would at least try to ^^

Thanks mates, we will treat this now like this.

Ouch. I completely missed that section, despite my many years of GMing in multiple 40k systems - thanks for pointing it out! That means that standard Marines all get a -40 to all Concealment and Silent Move tests. Hmm, my team won't like that

In this case OP is right. Guerilla Training says "The Battle-Brother does not take the penalties to Silent Move and Concealment normally inflicted by power armour" - that must include the -30 for wearing a 7+ AP armour.

This makes sense though. A marine in power armour is not stealthy by any means given its about half a ton worth of character. It's like trying to hide a tank...doable but takes specialist training but this is why you have scout armour to offset that and your Kill Team need to usually consider whether they want the protection of the armour and will take the stealth hit or whether they want to go scout armour to be more sneaky and risk getting hit.

Actually, Scout Armour also provides a +10 Bonus to concealment tests. Combined with a masking screen you have +40 concealment/+30 silent move, so even without skilling concealment/silent move, you have a good chance of going undetected.